/*
 *   This program is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation, either version 3 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/*
 *    SelectedTag.java
 *    Copyright (C) 1999-2012 University of Waikato, Hamilton, New Zealand
 *
 */

package weka.core;

import java.io.Serializable;
import java.util.HashSet;

/**
 * Represents a selected value from a finite set of values, where each value is
 * a Tag (i.e. has some string associated with it). Primarily used in schemes to
 * select between alternative behaviours, associating names with the alternative
 * behaviours.
 *
 * @author <a href="mailto:len@reeltwo.com">Len Trigg</a>
 * @version $Revision$
 */
public class SelectedTag implements Serializable {

    private static final long serialVersionUID = 6947341624626504975L;

    /** The index of the selected tag */
    protected int m_Selected;

    /** The set of tags to choose from */
    protected Tag[] m_Tags;

    /**
     * Creates a new <code>SelectedTag</code> instance.
     *
     * @param tagID the id of the selected tag.
     * @param tags  an array containing the possible valid Tags.
     * @throws IllegalArgumentException if the selected tag isn't in the array of
     *                                  valid values or the IDs/IDStrs are not
     *                                  unique.
     */
    public SelectedTag(int tagID, Tag[] tags) {
        // are IDs unique?
        HashSet<Integer> ID = new HashSet<Integer>();
        HashSet<String> IDStr = new HashSet<String>();
        for (int i = 0; i < tags.length; i++) {
            Integer newID = new Integer(tags[i].getID());
            if (!ID.contains(newID)) {
                ID.add(newID);
            } else {
                throw new IllegalArgumentException("The IDs are not unique: " + newID + "!");
            }
            String IDstring = tags[i].getIDStr();
            if (!IDStr.contains(IDstring)) {
                IDStr.add(IDstring);
            } else {
                throw new IllegalArgumentException("The ID strings are not unique: " + IDstring + "!");
            }
        }

        for (int i = 0; i < tags.length; i++) {
            if (tags[i].getID() == tagID) {
                m_Selected = i;
                m_Tags = tags;
                return;
            }
        }

        throw new IllegalArgumentException("Selected tag is not valid");
    }

    /**
     * Creates a new <code>SelectedTag</code> instance.
     *
     * @param tagText the text of the selected tag (case-insensitive).
     * @param tags    an array containing the possible valid Tags.
     * @throws IllegalArgumentException if the selected tag isn't in the array of
     *                                  valid values.
     */
    public SelectedTag(String tagText, Tag[] tags) {
        for (int i = 0; i < tags.length; i++) {
            if (tags[i].getReadable().equalsIgnoreCase(tagText) || tags[i].getIDStr().equalsIgnoreCase(tagText)) {
                m_Selected = i;
                m_Tags = tags;
                return;
            }
        }
        throw new IllegalArgumentException("Selected tag is not valid");
    }

    /**
     * Returns true if this SelectedTag equals another object
     * 
     * @param o the object to compare with
     * @return true if the tags and the selected tag are the same
     */
    public boolean equals(Object o) {
        if ((o == null) || !(o.getClass().equals(this.getClass()))) {
            return false;
        }
        SelectedTag s = (SelectedTag) o;
        if ((s.getTags() == m_Tags) && (s.getSelectedTag() == m_Tags[m_Selected])) {
            return true;
        } else {
            return false;
        }
    }

    /**
     * Gets the selected Tag.
     *
     * @return the selected Tag.
     */
    public Tag getSelectedTag() {
        return m_Tags[m_Selected];
    }

    /**
     * Gets the set of all valid Tags.
     *
     * @return an array containing the valid Tags.
     */
    public Tag[] getTags() {
        return m_Tags;
    }

    /**
     * returns the selected tag in string representation
     * 
     * @return the selected tag as string
     */
    public String toString() {
        return getSelectedTag().toString();
    }

}
